Variable capacity pump



H. CENTERVALL VARIABLE CAPACI}TY .PUMP

Feb; 19, 1935. 1,991,377

- Filed Mafch 24, 1932 v 2 Sheets-Sheet 1 INVENTOR H. CENTER\ILL r 1,991,377

VARIABLE CAPACITY PUMP Filed March 24, 1932 2 Sheets-Sheee- 2 .m&NN

( INVENTOR %/P A M, W ATTORNEY y 35 showing alternative embodiments of portions of The cylinder body 31 is rotat y ou p Ptented Feb. 19, 1935 y b I k r Y A V UNITED STATES PATENT OFFICE VARIABLE CAPACITY PUMP A Hugo Centervall, Brooklyn, N. Y., assgnor to .Manly Corporation, New York,.N. Y., a. corporation of Delaware' Application March 24, 1932, Serial No. 600,914 u 2i Claims (Cl. 103-161) This invention relatos to improvements in together by bolts 13. The enclosing casing forms 'pumps or fluid motors of the type having rotatthe support for the device and the member 11 ing radial cylinders and a non-rotatable valve is accordingly provided with feet 14. Both of member. the members 11 and 12 are provided with fins 5 The principal object of the invention is to pro or ribs 15 to facilitate radiation. 5

vide an improved pump o r motor of this type that The rear member 11 is formed with a hub 16 is simple, relatively inexpensive to manufacture, Wh0se Dreferably tapered b is p d to ecompact and ,easy to assemble and disassemble. ceive one end of the stationary cylndrical valve The improvements constitutng the invention member 20 which is keyed against rota icn by 1oare particularly useful-in pumps ard motors of a cap screw 17, as shown in Figure 3. The valve variable capacity such as are used for power m m r 0 is eld in place lengthwse0f the hub transmission for accurate speed control or to 16 by nuts 19, as indicated in dotted lines in obtain variabletorque, but may be employed with 2on the outer ends of the threaded studs 18 .advantageinpumps and mot r of fixed capacity. which pass through suitable openings in the Other and more specific objects will appear rear cover plate lo and whose inner ends are 15 from the following description of an.illustrative u d in the Valve member 20. (F g. 3). embodiment of the present invention. F h purp se of this d s pti n th struc- In the drawings: ture will be considered asa pump. Figure 1 is a transverse view, partly i ti The valve member 20 is provided With the usual 0 of a pump or motor constructed ill accordance Valvep0rts 21 22 Which are separated y a with the present invention and taken along the t ansv a d 23. L ud a passa s 25 line l-1 of Figure 2. and 26 lead from the valve ports 21 and 22 ref Fig. 2 is a central longitudinal view along the spectively and extend thw se in the Valve line 2-2 of Fig. 1; member 20 .from said valve ports through its 25 Fig. 3 is a transverse sectional view along the real end n h h b 1 f th m m er 11. The 25 line 33 of Fig. 2; rear cover plate 10 is likewise formed With two Fig. 4 is an elevation of one of the cormecting passages 7 and 28 adapted to re W h the rod members as viewed lengthwise pi the device; passages 5 and respectively, d to t e Out r Fig. 5 is an elevation of one of the connecting ends of said P sages 27 and 28 are attached ap- 30 rod members as viewed transversely of the propriate p ect s 9 and 30, respecdevice; tively. With the parts in the position shown in Fig. 6 is a top plan view of one of the connectthe drawings and r0tating to the r ht, r locking rod members; and v Wise, as shown in Fig. 1? the port 21 constitutes Figs. 7 and 8 are Ira'gmentary sectional views S11Ct0n and the p t 22 the P u re port.

the connecting rod member. the valve member 20 and for this purpose is pro- Bef0re explaining the present inventon, it is vided with a central bore .32, the fit of the parts to be understood that the invention is not limited bein su h as t it t y ind r b dy 31 t in its application to' the details of construction rotate fr ly Whil f rm a substantally fluid and arrangement of parts described herein and tight runnin j i T the cy1nder y 31 is Ilustrated in the accompanying drawings, since v attached by pin 33 and p ScreWs 34 a flange the Invention is capable of other embodiments 35 on one end of the revoluble' shaft 36 which and of being practiced and carried out in varipasses through an appropriate opening in the 11 W ys. It is also to be understood that the front casing member 12, suitable packing 37 being phraseology or terminology used herein is for the used to prevent leakage. The shaft 36 constitutes 45 purpose of description and not for limitaton, the driving shaft in case the apparatus is used and it is not intended to limit the inventio'n beas a pum'p and the driven shaft when used as a yond the terms of the several claims hereto ap-, motor. The cylinder body 31 is provided with a pended as considered in view ol the prior art plurality of radially disposed cylinders 38 having and the requirements thereof. v ports 39 on their inner ends adapted to register Reterring now to the drawings, 9 indicates with the valve ports 21 and 22 in the valve memt e enclosing casing which is preferably formed ber 20, said ports 39 being preferably less in area in two portions and as here shown comprises a thanthe area of the cylinders 38. The cylinder rear member ll to which is securely attached-a body 31 ispreferably formed of one solid body 5 front memberl2, the two members being held and the number of cylinder's is preferably five, 55

although this number may be more or less, as

desired.

Slidable within the cylinders 38 are pistons 40,

here shown as hollow, which are provided With,

piston pins 41 extending through slots 42 in the outer ends of the walls of said cylinders 38 and positioned substantially parallel with the axis of rotation of the cylinder body 31. The pistons 40 and the piston pins 41 are held together by pins 43, preferably made of bronze, which are kept in place by the walls of the cylinders 38, the proportions of the parts being such that the pins 43 are within the bore of the cylinders 38 at all points of the stroke of the pistons 40.

For each piston 40 there is provided a connecting rod member 45 which is preferably made of bronze, although other materials or a combination of materials may,obviously be used if preferred. This connecting rod member 45 Which constitutes one of the novel and important features of my improved structure is shown in detail in Figs. 4, 5 and 6. In the present embodiment the connecting rod member 45 consists primarily of a sleeve 46, of generally elliptical cross section, which surrounds the cylinder with its longer diameter transverse to the axis of rotation to allow a limited rocking motion of the member 45 with respect to the cylinder. Projecting axially at the inner face of each sleeve 46 are shoes 48 of arcuate configuration and with their outer faces curved to fit within the inner faces of the inner races 56 of the beaiing assemblies 57. The shorter diameter of the elliptical sleeves 46 corresponds with the outer diameter of the cylinders 38 and each sleeve is fitted to its cylinder so as to have a freely sliding contact with the wall of the cylinder or with a face formed on its outer wall. The outer ends of the sleeves 46 are provided at the sides with hubs 47 bored to receive the ends of the piston pin 41.

The shoes 48 are held in place With respect to said inner circumferential surfaces of the races 56 by retainer rings 51 which are received within segmental channels 49 formed in the inner faces of the ends of the shoes 48 which preferably project outwardly beyond the said races 56. In order to secure compactness, the ends of the piston pins and the hubs 47 are cut away flush with the outer surface of the tubular member 46' to a point slightly beyond the middle of the pins to permit them to clear the slideways 61 which Will be described later. This cutting away does not reduce the useful bearing surface for the reason that the pressure is outward on the pistons and hence the inner sides of said piston pins 41 and said hubs 47 are never subject to heavy pressures. The arrangement is such that the piston pins 41 may turn freely in the hubs 47 and the shoes 48 may slide upon the inner circumferential surfaces of the races 56 so that the connecting rod member 45 may properly adjust itself to compensate for its varying angularity with respect to the cylinder 38 and the piston 40 during the stroke of said piston 40.

In operation, the races 56 rotate substantially with the piston assembly so that the only movement of the shoes 48relative to the races 56 is the slight amount necessary tocompensate for angularity of the connecting rod member 45, and as the races 56 and the shoes 48 are positioned relatively near the center of rotation, this relative movement is very small. While the connecting rod member 45 has been shown herein as integrally formed, it Will be obvious that it may be made in properly connect d sections if desired.

While oil vapor (as oil is the fluid usually en!- ployed) within the enclosing casing will ordinarily furnish sufiicient lubrication for the shoes 48, there is provided additional lubricating means for this purpose. The inner faces of the shoes 48 are recessed to form pockets 52 connected by passages 53 with the outer faces of said shoes 48 which bear against the inner circumierential surfaces of the races 56. The end of the cylinder bouy 31 adjacent the hub 16 of the casing member 11 is cut away to form a, taper 54 and the end of said cylinder body 31 adjacent the flange 35 is provided with a plurality of angularly. drilled holes 55 leading from the space between the end of the valve member 20 and the said fiange 35. Fluid leaking out of the valve ports 21 and 22 and the cylinder ports 39 will pass out toward the ends-of the bore 32 of the cylinder body 31 and the arrangement is such that centrifugal force produced by the rotating cylinder body 31 will cause such leakage fluid to be thrown, by the taper 54 and the angular holes 55, into the pockets 52 whence it will pass through the passages 53 to the outer faces of the shoes 48 and the inner circumferential surfaces of the races 56.

Each bearing assembly 57 is carried by a later' ally movable slide 60 which is formed to receive the outer race 58. Each slide 60 is supported upon parallel transverse slideways 61, one such pair of 'slideways 61 being formed in the inner side of the casing inemberl2 and another such pair being formed in the opposing inner side of the casing member 11. The slideways 61 are partially cut away in the middle, asshown in Fig. 1, to provide clearance for the rotating cylinder and piston assemblies in a device of compact design. The two slides 60 are fastened together in order to secure uniformity of their movement and position, and for this purpose each slide 60 is provided on both its ends with guide studs 62 which project through suitable openings in covers 63 which close appropriate openings in the sides of the casing member 11. The outer ends of the guide studs 62 pass through holes in the cross-heads 64 and are held in place with respect to it and with respect to each other by means of nuts 65 in cooperatio with shoulders 66 formed on said guide studs 62. The inner surfaces of the covers 63 form stops for the reduced ends 67 of the slides 60, as shown in Fig. 1. Lateral movement of the slides 60 may be effected by any preferred means, such as an appropriate screw and nut device, not shown, but which is connected to one of the cross heads by a stud 68.

The position of the inner races 56 of the bearing assemblies 57 determines the length of the stroke of the pistons 40 and the direction of flow of the fiuid. Hence, by movement of the slides 60 the stroke of the pistons 40 may be inflnitely varied at will from zero (when the slides 60 are in their middle position and the axis of rotation of the cylinder body 31 and the centers of the races 56 are coincident) to maximum (when the slides 60 are in their extreme outward positions). The direction of flow of the fiuidmay obviously be reversed by moving the slides 60 from one side to the other of their middle or zero stroke position.

Where a fixed stroke of the pistons is desired, it will be obvious that the bearing assemblies 57 may be carried upon any suitable non-movable supports such as annular recesses formed in the casing member 12 and in the rear wall of the casing member 11 and adapted to receive the outer races 58.

An alternative design of the shoes 48 of the connecting rod member 45 and their associated parts is shown in Fig. 7. In this embodiment a ring 70 is fitted within each race 56 in sucha manner that its inner edge projects beyond the inner face of said race 56. The shoes 48 are slidably disposed against the inner circumferential surface of this ring 70 and the sides 46 are modifled' to contain segmental grooves 71 which receive the inner edge of the ring 70 which functions as a retainer ring. The rings 70 are preferably made of such Width and so positioned that their outer edges project beyond the outer faces of the races 56 an amount equal to the already described inward projections in order that there may be substantially equal j bearing surfaceon each side of the center of each of the bearing assemblies 57. v

Fig. 8 shows a second alternative embodiment of this part of the device. In this instance the side walls of the connecting rod member 46 are formed with outwardly ,projecting segmental flanges 73 which are received within annular channels '74 recessed in the inner or opposing faces of the inner races 56 of each ofthe bearing assemblies 57. Thechanneis 74 cause the bearing races 56 to act as retainer rings and prevent the inward radial movement of the connecting rod members45, thus maintainng the shoes 48 in proper position.with respect to the races56.

The operation of the device will be readily understood. The cylinder member 31 with the radial cylinders 38 rotates about the stationary valve member 20 as a center while the connecting rod members 45 rotate around the center of the bearing .assembly 57; hence if the slides 60 are adjusted to displace the bearings out of exact concentric relation with the valve member the pist0ns 40 and connecting-rod members 45 will be reciprocated radially of the cylinders, threby drawing the oil or other liquid into the cylinders on the outward movement of the pistons and expelling the oil on the inward movement. The stationary valve member 20, as shown in Fig. 1, is cut away on its upper side sufficiently for all the cylinders to be connected to the common intake port 21 during the outward movement of the pistons, and is similarly cut away on its lower side to thereby connect all the cylinders to the common delivery port 22 on the inward movement of the pistons, assuming the direction of rotation and adjustment of the parts to be as indicated. If the Slides 60 are adjusted toward the left as shown in l 'ig. 1, to shift the center of rotationof the bearing assembly 57 to the left of the center of the valve member 20, the pistons will obviously move inwardly instead of outwardly while the cylinders are in fluid-transmittng con- 'nection with.the .port 21, thus connecting that port into the discharge port'of the pump and the port 22 into the suction 'port. If the pump is used as a source of fluid under pressure for operating an hydraulic motor this reversal of the direction o! flow of liquid in the ports 21 and '22 will serve to reverse the direction of rotation of the motor shaft. Also the extent to which the bearing assembly 57 is adjusted out of concentric relation with the valve member 20 determines the length of the piston stroke and consequently the capacity of the pump and the speed and torque of the hydraulicmotor as described, for example, in the patent of Chas. M. Manly, No. 1,266,606, granted May 21, 1918. y

The pump or motor of this application is primarily an improvement'over ,the pump and motor described in the Manly patent. Its princi-- they are to be subjected.

pal advantagesare the greater simplicity of de-. sign with an eliminaton o! a great many parts. The design is particularly adapted tor ease of assembly. In assen1bling the pump the pistons with their connecting rod members connected thereto are placed in their cylinders. The rings 51 are then mounted in the grooves in the inner, faces of. the shoes 48. The previously assembled ball bearings are then assembled over the shoes 48, thus connecting all the connecting rod members together into a single unit. The assembly unit is then slipped over the valve member and the outer race of the bearing adjacent the hub 16 fitted into its slide 60, or the slide may be fitted over the bearing before the assembly is mounted on the stationary vlve member and the slide fitted into its slideway when the cylinder block is pushed back of the valve member to bring the ports 39 of the cylinders into alignment with the One particular advantage of the present construction is the elimination of substantially all sliding friction between parts whose surfaces are under pressure. The pressure on,the stationary valve member is substantially balanced by the pressure in the cylinders due to the ports 39 being of less area than the ends of the cylinders. Hnce the only friction between plainbearings on parts under pressure is the friction incidental to the rocking movement of the cohnectingrod members and, as will.be observed from Fig. 1 of the drawings, this movement is of such slight extent as to be practically negligible.

By the a1rangement of the two main bearings symmetrical with respect to'the plane of the centers of the cylinder, all torsional strains are eiiminated. Also, as the connecting rod members and bearings are external to the cylinder assembly, theymay be as large and rugged as necessary to readily transmit the load to which I claim:

1. In a pump or motor, the combination of a rotating cylinder structure having a plurality of radial.cylinders, pistons therein, a sleeve mem ber surrounding each cylinder pivotally connected to the outer end of the.piston thereof, a me mber rotaftable about an axis eccentric with respect to the axis of rotation 'of the cylinder body, and means connecting said sleeve members to said rotating member for rotating movement therewith and relative circumerential move ment with respect thereto.

2. In a pump or motor of the class described, the combination of. a rotating cylinder member having rotating cylinders; pistons thereii1, and means tor reciprocating said pistons upon the rotation of said cylinder member,- said means comprising connecting rods pivotally connected to the outer ends of said pistons, said connecting rodsconsisting of sleeve memrers surrounding said cylinders and having axially projectihg shoes, a rotating ring surrounding said shoes,

and a bearing eccentric to the axis of rotation the combination of a stationary valve member,

acylinder body having' radial cylinders rotatably mounted on said'valve member, pistons mounted in said cylinders, connecting rod members pivotally attached to theouter ends of said cylinders, said members comprising sleeves surrounding said cylinders, the diameter of said sleeves in the plane of rotation being suflicient to permit oscillation of said members With respect to the cylinders, shoes projecting axially from one side of said sleeves, the outer faces of said shoes being shaped to a common curvature, a rotating ring surrounding said shoes, means for holding said shoes in sliding contact with the inner circum- Ierence of said ring, and a bearing eccentric to the axis of rotation of said cylinders for supporting said ring. r

4. In a pump or motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arrangedcylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of freely rotatable rings and a connecting rod member for each piston, said connecting rod member comprising a plurality' of portions radially disposed with respect to said rings, the outer ends of which are operatively connected with said piston and the inner ends of which are operatively connected with said rings, and means rigidly connecting said radially disposed portions.

5. In a purfip or motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of freely rotatable rings, and a connecting rod member for each piston, said connecting rod member comprising a plurality of portions radially disposed with respect to said rings, one of the ends of which are rockably connected with said piston and the other ends of which are adapted to form shoes slidably bearing against said rings without definite attachment thereto, and means rigidly connecting said radially disposed portions.

6. In a pump or motor, a. central cylindrical non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of rings positioned eccentrically with respect to the axis of rotation of said cylinder body, and a connecting rod member for each.

piston, said connecting rod member comprising a plurality of portions radially disposed with respect to said rings, one of the ends of which are rockably connected With said piston and the other ends of which are adapted to bear against the inner side faces and inner circumferential surfaces of saidrings without definite attachment thereto, and means rigidly connecting said radially disposed portions.

7. Ina. pump or motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of freely rotatable rings, a connecting rod member for each piston, said connecting rod member comprising a plurality of rigidly joined portions radially disposed with"respect to said rings, the outer ends of which arebperatively connected with said piston and the inner ends of which are operatively connected with said rings but without definite maintaining said connecting rod member n proper relation to said rings.

8. In a pump or motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a. plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of movably supported rings, means for moving said rings to vary their centers with respect to the center of rotation of said cylinder body and a. connecting rod member for each piston, said connecting rod member comprising a plurality of portions radially disposed with respect to said rings, the outer ends of which are operatively connected with said piston and the inner ends of which are operatively connected with said rings, and means rigidly connecting said radially disposed portions.

9. In a pump or motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable body having a plurality of radially arranged cylinders, ports in said cylindersadapted to register with said valve ports, pistons in said cylinders, a plurality of movably supported rings, means for moving said rings to vary their centers With respect to the center of rotation of said cylinder body, and a connecting rodmember for each piston, said connecting rod member comprising a plurality of portions radially dis posed with respect to said rings, one of the ends of which are rockably connected with said piston and the other ends of which are adapted to form shoes slidably bearing against said rings without definite attachment thereto, and means rigidly connecting said radially disposed portions.

10. In a pump or, motor, a non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of movably supported rings, means for moving said rings to vary their centers with respect to the center of rotation of said cylinder body, a connecting rod member for each piston, said connecting rod member comprising a. plurality of rigidly joined portions radially disposed with respect to said rings, the outer ends of which are operatively connected with said piston and the inner ends of which are operatively connected with said rings but without definiteattachment thereto, and means continuously maintaining said connecting rod members in proper relation to said rings.

non-rotatable valve member having ports tor the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of movably supported rings, means for moving said rings to vary their centers with respect to the center of rotation of said cylinder body, a connecting rod member for each piston, said connecting rod member comprising a plurality of rigidly joined portions radially disposed with respect to said rings,- the outer ends of which are rockably connected with said piston and the inner ends of which are adapted to bear against the inner side faces and the inner circumferential surfaces of said rings without definite attachment thereto and means continuously maintaining said connecting rod members in proper relation to said rings.

attachment thereto, and means for continuously l, 12. In a pump or motor, a central cylindrical 75 non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of -radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a pair of bearing assemblies having inner and outer races and positioned eccentrically with respect to the center of rotation of said cylinder body, a connecting rod member for each piston, said connecting rod member comprising a pair of rigidly joined portions radially disposed with respect to said bearing assemblies whose outer ends are rockably connected with said piston and whose inner endsare adapted to form segmental shoes slidably bearing against the inner circumferential surfaces of said inner races Without definite attachment thereto, and means continuously maintaining said shoes in proper position with respect to said inner races.

13. In a pump or motor, acentral cylindrical non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to 'register with said valve ports, pistons in said cylinders, a pair of movably supported bearing assemblies having inner and outer races, means for moving said bearing assemblies to vary their centers with respect to the center of rotation of said cylinder body, a connecting rod member for each piston, said connecting rod member comprising a pair of rigidly joined portions radially disposed with respect to said bearing assemblies whose outer ends are roekably connected with saidpiston and whose inner ends are adapted to form segmental shoes slidably bearing against the inner circumferential surfaces of said inner races without definite attachment thereto, and means continuously maintaining said shoes in proper position with respect to said inner races.

14.In a pump or motor, a central cylindrical non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially disposed cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of rings eccentrically positionable with respect to the axis of rotation of said cylinder body, means for varying the centers of said rings With respect to the axis of rotationot said cylinder body, and a connecting rod member for each piston operatively connecting said piston With said rings, said connecting rod member comprising a plurality of rigidly joined portions radially disposed with respect to said rings whose.outer ends are rockably connected with said piston and whose inner ends are adapted to slidably cooperate with said rings, but without deflnite attachment to said rings, in such a manner as to substantially prevent lengthwise and outwardly radial movement. of said connecting rod member with respect to said rings.

15. In a pump or motor, a central cylindrical non-rotatable valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially disposed cylinders, ports in said cylinders adapted to register With said valve ports, pistons in said cylinders, a plurality of rings eccentrically positionable with respect to the axis of rotation of said cylinder body, means for vajrying the centers of said rings with respect to the axis of rotation of said cylinder body, a connecting rod member for each piston operatively connecting said piston with said rings, said connectingrod member comprising a plurality of, rigidly joined portions radially disposed with respect to said rings whose outer ends are rockably connected with said pistons and whose inner ends are adapted to slidably cooperate with said rings, but without deflnite attachment to said rings, in such a manner as to substantially prevent lengthwise and outwardly radial movement of said connecting rod member with respect to said rings, and separate means substantially preventing the inwardly radial movement of said connecting rod members with respect to said rings.

16. In a pump or motor, a cylindrical valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said*cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of rings r0- tatable in company With said pistons, a connecting rod member for each piston comprising a plurality of rigidly joined portions radially disposed with respect to said rings and whose outer ends are operatively connected with said pistons and whose inner ends are adapted to form shoes slidably bearing against the inner circumferential surface s of said rings, and means for lubricating the bearing surfaces of said rings, said lubricating means comprising passages from the Outer to the inner faces of said shoes, pockets in the inner faces of said shoes communicating with said passages and means whereby fluid leaking out of said valve ports and said cylinder ports is supplied to said pockets by centrifugal foroe produced by the rotating parts. V,

17. In ,a pump or motor, a cylindrical valve member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of bearing assemblies having inner andouter races, an annular channel in the inner face of the inner race of each of said bearing assemblies, and a connecting rod member for each piston operatively connecting said piston with said bearing assemblies, said connecting rod member including a plurality of rigidly joined portions radially disposed with respect to said bearing assemblies and said radially disposed portions having segmental flanges adapted to be received within said an' nular channels in said inner races of said bearing assemblies.

,18. In a pump or motor, a cylindrical valve member having ports for the passage f fluid, a rotatable cylinder body having a plurality of radially arranged cylinders, ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of bearing assemblies having inner andouter races, a ring within each of said inner races of greater Width than said races and projecting inwardly toward said cylinder body, and a connecting rod member for each piston operatively connecting said piston and said rings, said connecting rod member including a plurality of rigidly joined portions radially disposed with respect to said rings and having segmental channels. adapted to receive said rings.

19. In a pump or motor, a cylindrical member having ports for the passage of fluid, a rotatable cylinder body having a plurality of radially arranged cylinders,ports in said cylinders adapted to register with said valve ports, pistons in said cylinders, a plurality of rings rotatable in company with said pistons, a plurality of retainer rings, and a connectng rod member for each piston, said connecting rodmember including a plurality of rigidly joined portions radially disposed with respect to said first named rings whose A outer ends are operatively connected with said piston and whose inner ends are adapted to form. shoes slidably bearing against the inner circumferential surfaces of said first named rings, said shoes having segmental channels for receiving said retainer rings.

20. In a pump or motor, the combination of a rotating cylinder structure having a plurality of radial cylinders, pistons therein, a. pair of connecting rod members disposed on oppo'site sides of each cylinder each comprising a. body portion, two end portions and means at least in part interposed between adjacent cylinders for rigidly connecting said body portions, means for pivotally connecting the outer end portions of each pair of said connectng rod members to the outer end of one of said pistons, a member rotatable about an axis eccentric with respect to the axis of rou tation of the cylinder structure, and means connecting the inner end portions of each pair of connecting rod members to said rotatable member for rotating movement therewith and relative circumferehtial movement with respect thereto.

21. In a pump or motor, the combination of a rotating cylinder structure having a plurality of radial cylinders, pistons therein, a pair of connecting red members disposed on opposite sides of each cylinder each comprising a body portion, two end portions and a connecting member disposed inwardly of the end portions rigidly connecting said body portions, means for pivotally connecting the outer end portions of each pair of said connecting rod members to the outer end of one of said pistons, a member rotatable about an axis eccentric With respect to the axis of rotation of the cylinder structure, and means connecting the inner end portions of each pair of connecting rod members to said rotatable member for rotating movement therewith and relative circumferential movement With respect thereto.

HUGO CENIERVALL. 

